(Because everyone does $50, which makes it so very much less fun.)
I don’t know about your mothers, but mine is ridiculously difficult to buy for. She doesn’t wear makeup or perfume, she doesn’t have a particular affinity for flowers, she has no definable hobbies aside from, possibly, home repair (it’s just a suspicion; she’s never confirmed or denied it outright), and she has no inclination toward any type of electronic.
If your mum’s a little easier to buy for, though, here are ten last-minute beauty gift ideas under $40. Because makeup is a great way to spoil oneself, but (I know this, at least, is true for my mother) sometimes our mums and dads need someone else to do the spoiling, you know?